Monday, of course
7000/7 = 1000 with a remainder of 0. That means that, in 7000 days, the day of the week will be the same as it is today.
9,000 days is 5 days more than 1285 weeks, so the day of the week in 9000 days will be five days earlier in the week, or two days later in the week, than it is today. As an example, if today is Wednesday it will be Friday in 9,000 days.
Let Yesterday=-1 Today=0 Tomorrow=1 the day after yesterday=(-1)+1=0=Today the day before the day after yesterday=(-1)+[(-1)+1]=(-1)=Yesterday !!! Answer = Yesterday
Wednesday
The 12th August 1964 was a Wednesday.
Wednesday
7000/7 = 1000 with a remainder of 0. That means that, in 7000 days, the day of the week will be the same as it is today.
If today is Wednesday it will be Saturday 136 days (19 weeks and 3 days) from today.
Also Wednesday 7 x 17 = 119
It will be Saturday.
Friday
If today is Wednesday, it be a Saturday if there is no leap year, or a Sunday if there is a leap year, within the next 1249 days.
Thursday
Friday.
Tuesday
Five days after Wednesday is Monday. So if Monday is the day after tomorrow, today is Saturday.
7 or 14 or 21 or 28 days ago was also Wednesday 29 = Tuesday 30 = Monday